LANE KEEPING ASSISTANCE SYSTEM

Abstract

A lane keeping assistance system including: means for determining a first position of the vehicle in a network with a first accuracy; first interface for providing trajectory of the vehicle in the network; second interface for providing position data of right boundary objects and position data of left boundary objects, and radar signatures of these boundary objects; radar system to scan right and left lateral environment of the vehicle and determine distances to objects on a right of the vehicle and radar signatures thereof, and distances to objects on a left of the vehicle and radar signatures thereof; evaluation unit to perform identification of acquired objects based on the first position, the provided data, and the determined data, and to determine a second position of the vehicle with a second position accuracy; and control device to control the vehicle taking into consideration the target trajectory and the second position.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the U.S. National Phase of, and Applicant claims priority from, International Patent Application No. PCT/EP2016/067584, filed on 22 Jul. 2016, and German Patent Application No. DE 10 2015 111 925.0, filed on 22 Jul. 2015, both of which are incorporated herein by reference in their entirety.

BACKGROUND

Field

The invention relates to a lane keeping assistance system, to a vehicle having such a lane keeping assistance system, and to a method for the transverse control of a vehicle.

Discussion of Related Art

Lane keeping systems are known in the prior art. Simple lane keeping systems generate, for example, haptic signals on the steering wheel, when the vehicle is about to exit a current lane. Thus, the driver can correct the transverse control of the vehicle by corresponding steering inputs. More complex lane keeping systems are, in particular, systems for the autonomous transverse control of the vehicle and they are used to autonomously guide the vehicles on a predetermined trajectory, for example, a traffic lane, a predetermined lane change, a predetermined entry or exit, etcetera.

Known lane keeping assistance systems are based substantially on the acquisition and evaluation of optical environment data, here, in particular, traffic lane markings. However, the traffic lane markings may not be recognizable due to soiling, snow cover, or other environmental influences (for example, dense fog).

SUMMARY

The aim of the invention is to indicate an improved lane keeping assistance system.

The invention results from the features of the independent claims. Advantageous developments and designs are the subject matter of the dependent claims. Additional features, application possibilities, and advantages of the invention result from the following description and from the explanation of embodiment examples of the invention, which are represented in the figures.

A first aspect of the invention relates to a lane keeping assistance system for a vehicle. The proposed lane keeping assistance system includes: a first means for determining a current first position P1(t) of the vehicle in a road traffic network with a position accuracy ΔP1: P1(t)=P1(t)±ΔP1, a first interface for providing a target trajectory ST(t) of the vehicle in the road traffic network, a second interface for providing georeferenced position data P_OR,i, P_OL,i of objects OR_i of a right traffic lane boundary and georeferenced position data of objects OL_i of a left traffic lane boundary, and 2D or 3D radar signatures RS_OR,i and RS_OL,i of these objects OR_i, OL_i for the route section of the road traffic network being traveled by the vehicle, wherein the georeferenced position data P_OR,i, P_OL,i have a position accuracy ΔP2, where ΔP2<ΔP1, i=1, 2, 3, . . . , a radar system for scanning a right and a left lateral environment of the vehicle for determining distances D_OR to objects OR present laterally to the right of the vehicle and the radar signatures RS_OR thereof, and distances D_OL to objects OL present laterally to the left of the vehicle and the radar signatures RS_OL thereof, an evaluation unit, via which initially, based on the first position P1(t), the provided data P_OR,i, P_OL,i, RS_OR,i and RS_OL,i, and the determined data D_OR, RS_OR, D_OL, RS_OL, an identification of the determined objects OR and OL as objects OR_i, OL_i is performed, and based thereupon, a second position P2(t) of the vehicle is determined, the position accuracy of which has the position accuracy ΔP2, at least in one dimension, and a control device for the transverse control of the vehicle, via which the transverse control of the vehicle is performed, taking into consideration the target trajectory ST(t) and the position P2(t).

The first means is advantageously designed for the determination of the position P1(t) based on data of a satellite navigation system, or based on optical environment data of the vehicle, or based on radar data, or based on dead reckoning data, or a combination thereof. Advantageously, the first means includes a GPS, a Galileo, and/or a GLONASS receiver unit. The position P1(t) is determined with a position accuracy ΔP1: P1(t)=P1(t)±ΔP1 which can vary, for example, in the case of a GPS-based navigation system, in a range between 5 and 150 m. This position accuracy is not sufficient, in particular, for autonomous vehicle operation.

Via the first interface, the target trajectory ST(t) of the vehicle is provided advantageously by a navigation system or a central system of the vehicle, or by an external central traffic control center (for example, a central server to which the vehicle is connected for the data exchange). The target trajectory ST(t) depends on the time t and provides the upcoming target route of the vehicle, preferably in georeferenced coordinates. Naturally, other reference systems are also conceivable.

A target trajectory ST(t_k) predetermined for a time step t_k can be provided for an upcoming time step t_k+1 via the first interface in modified form, for example, in order to take into consideration a temporally changing traffic situation, the temporally changing position P1(t) and/or P2(t) of the vehicle, also in relation to environment objects, a temporally changing vehicle state (for example, energy reserve), a predetermined new destination, etcetera. In particular, a target trajectory ST(t) can be changed based on the behavior of another traffic participant and on suddenly occurring unknown obstacles. How a target trajectory ST(t) is to be changed is not a subject matter of the present application. Instead, it is assumed here that, at each time t or for each time step t_k, a target trajectory ST of an upcoming target travel route for the vehicle is provided.

Via the second interface, the georeferenced position data P_OR,i, P_OL,i of objects OR_i, OL_i and the associated 2D or 3D radar signatures RS_OR,i and RS_OL,i, of these objects OR_i, OL_i are advantageously provided for the route section of the road traffic network being traveled by the vehicle, in particular, for the upcoming route section of the road traffic network, by a memory unit in the vehicle or by an external central server. In particular, the providing of the data P_OR,i, P_OL,i, RS_OR,i and RS_OL,i by the external central server has the advantage that the central server functions as a central database which is easier to update than a large number of memory units in vehicles. The georeferenced position data P_OR,i, P_OL,i provided via the second interface advantageously have a position accuracy ΔP2 of <0.05 m or <0.4 m or <0.3 m or <0.25 m or <0.20 m or <0.15 m or 0.10 m or <0.05 m.

With the radar system, the distances D_OR/D_OL to objects OR/OL present laterally to the right/left of the vehicle and the radar signatures RS_OR/RS_OL thereof are determined. The distances D_OR/D_OL advantageously indicate the horizontal distance of the objects OR, OL relative to a longitudinal axis of the vehicle. The radar system advantageously enables the determination of the distances D_OR/D_OL with an accuracy of <0.4 m or <0.3 m or <0.25 m or <0.20 m or <0.15 m or <0.10 m or <0.05 m. Moreover, the radar system advantageously enables the acquisition of the radar signatures RS_OR/RS_OL as 2D or 3D radar signatures.

For each of the objects OR_i/OL_i provided via the second interface, in addition to the georeferenced position data P_OR,i, P_OL,i, an associated 2D or 3D radar signature RS_OR,i/RS_OL,i is known, so that, via a comparison of the data acquired with the radar system and the data provided via the second interface, an identification of the objects OR/OL acquired by the radar system in each case as one of the objects OR_i, OL_i is possible.

This identification is performed by the evaluation unit. In the process, based on the first position P1(t), the provided data P_OR,i, P_OL,i, RS_OR,i and RS_OL,i, and the determined data D_OR, RS_OR, D_OL, RS_OL it is determined initially whether the determined radar signatures RS_OR, RS_OL can be unequivocally associated with the data provided. If such an unequivocal assignment is determined, the objects OL, OR are considered to have been identified as objects OR_i, OL_i.

Based on the measured lateral distances D_OR, D_OL to identified objects OR=OR_i and OL=OL_i to the vehicle, a second position P2(t) of the vehicle can then be determined, the position accuracy of which has the position accuracy ΔP2, at least in one dimension. This one dimension (direction) is defined by the vector of the respective determined horizontal distance between vehicle and the respective object OR/OL. In a coordinate system of the vehicle in which the x axis points in the direction of the current driving direction and the y axis points in a direction perpendicular thereto, wherein the x-y plane defines the horizontal plane, the position P2(t) of the vehicle accordingly can be indicated with a position accuracy ΔP2, at least along the y axis.

The position P2(t) is only determined if at least one lateral object OR or OL could be identified unequivocally. Since the objects OR/OL are arranged in-part irregularly in the lateral environment of the route section being traveled, the position is typically not determined continuously but point by point.

Advantageously, in the identification of the objects OL, OR as objects OR_i, OL_i in the evaluation unit, a plausibility verification is carried out, wherein the probabilities W(OR), W(OL) of an unequivocal identification of objects OR, OL in each case as one of the objects OR_i, OL_i are determined based on the determined radar signatures RS_OR and RS_OL, the provided radar signatures RS_OR,i and RS_OL,i, and the position P1(t). For the determination of the second position P2(t), only those acquired objects OR, OL are determined, the probabilities W(OR), W(OL) of which are above a predetermined limit value G1. For objects OR, OL, the probabilities W(OR), W(OL) of which are in each case below a predetermined limit value G1, a warning signal WARN is generated.

In this development, depending on the selection of the limit value G1 (for example, G1=90% probability), it can thus be ensured that the determined position P2(t) is robust and reliable or less robust and reliable. The generated warning signal WARN is advantageously used for marking unrecognized or unidentified objects OR, OL, which are stored in a data protocol of the evaluation unit. In particular, by using this plausibility verification, it is possible to detect whether a clear view onto the lateral environment of the vehicle or of the traffic lane was present, or whether the lateral environment is covered, for example, by other vehicles or vehicles traveling laterally with respect to the vehicle. In the last case, the probabilities W(OR), W(OL) are below the limit value G1, since the determined radar signatures and the determined distances of a vehicle traveling in an adjacent lane make it easy to distinguish the provided objects OR_i, OL_i.

Advantageously, via the second interface, data dependent on the current position P1(t)/P2(t) and on the driving direction of the vehicle is provided for the route section being traveled by the vehicle, in particular the upcoming route section. As a result, via the second interface, only currently relevant data is provided, so that the number of radar signature comparisons with objects OR_i, OL_i taken into consideration is limited, and thus the computation times required in the evaluation units are reduced.

The transverse control of the vehicle advantageously occurs autonomously, i.e., without steering intervention of the driver. The longitudinal regulation of the vehicle occurs preferably using known vehicle longitudinal regulation systems. The proposed lane keeping assistance system can advantageously be deactivated by the driver, preferably by a manual input or a voice input. Moreover, the transverse control is advantageously deactivated automatically, if a system error was detected, for example, due to a defect of one of the parts of the proposed lane keeping assistance system or in the case of unusable measurement data of the radar system over a pre-settable time period.

Advantageously, the transverse control of the vehicle is based on an additional consideration of data of known systems for the acquisition or scanning of the vehicle environment, such as, for example, optical systems (for example, for the determination of traffic lane markings, curbstones, etc.), ultrasound systems, laser systems, LIDAR systems, etcetera. This data of known systems is advantageously taken into consideration for the verification of the data determined by the radar system and/or if these known systems themselves can determine a georeferenced position of the vehicle, in which the determination of the position P2(t) is taken into consideration.

The objects OR_i, OL_i are advantageously firmly installed, for example, guardrails, vertical guardrail supports, curbstones, concrete deflectors, pylons, metal fences, noise control walls, sidewalls or radar reflectors, retroreflectors, corner reflectors, poles of traffic signs, overhead sign structures, and/or roadside emergency telephones. Such objects in each case have specific 2D/3D radar signatures which can be acquired and identified by the radar system of the vehicle.

Advantageously, the provided radar signatures RS_OR,i, RS_OL,i of the objects OR_i, OL_i are generated based on radar signatures which were acquired using a sensor on board an aircraft or a satellite in a top view onto the surface of the earth and subsequently converted into radar signatures which can be acquired horizontally. Radar sensors on board an aircraft or a satellite enable the acquisition of a road traffic network of a country in a short time, depending on the size, for example, within a day. Thus, a high-frequency updating of the corresponding radar targets of the lateral environment of traffic lanes can be ensured.

A development of the lane keeping assistance system is characterized in that, if the evaluation unit has determined the position P2(t) for a time step to, and for time steps t_k greater than t₀, where t_k=t_k−1+Δt, k=1, 2, . . . , and Δt:=time increment, the warning signal WARN is generated, the evaluation unit determines for these time steps t_k a position P2′(t_k), where

P2′(t_k)=P2′(t_k−1)+{dot over (P)}1(t_k−1)Δt, and  (1)

the control device carries out the transverse control of the vehicle at least for a predetermined period of time ZS based on the position P2′(t_k). The period of time ZS is selected advantageously depending on the speed of the vehicle from the range [10 s, 2 min]. This development assumes that for all the time steps after to no measurement results, which can be used for a determination of a position P2(t), are available.

Advantageously, via a third interface, data is provided, which enables an optical and/or ultrasound characterization of the objects OR_i, OL_i. Moreover, the vehicle advantageously includes an optical system OPT and/or an ultrasound system US, via which the right and the left lateral environment of the vehicle can be scanned, and via which corresponding distances D_R,OR,OPT, D_R,OR,US to objects OR present laterally to the right of the vehicle and corresponding distances D_L,OR,OPT, D_L,OR,US to objects OL present laterally to the left of the vehicle can be determined. Moreover, the optical system OPT and/or the ultrasound system US is/are advantageously designed to identify the acquired objects as objects OR_i or OL_i based on the optical data acquired by the respective system or ultrasound data. In this development, the evaluation unit for the determination of the second position P2(t) advantageously takes into consideration the determined distances D_R,OR,OPT, D_R,OR,US, D_L,OR,OPT, D_L,OR,US to the respective identified objects OR_i, OL_i. In this development, the objects OR_i and OL_i detected by the radar system are initially verified using an optical system OPT and/or an ultrasound system US.

A development of the lane keeping assistance system is characterized in that a transmission is made to a central station, indicating that with the radar system, at positions P1(t) or P2(t), objects OR and/or OL were determined, which are not identifiable as objects OR_i and/or OL_i and/or indicating that with the radar system, at positions P1(t) or P2(t), no objects OR and/or OL were determined, which, however, should be present as objects OR_i and/or OL_i. The central station is advantageously the station which provides the georeferenced position data P_OR,i, P_OL,i of objects OR_i and OL_i as well as associated 2D or 3D radar signatures RS_OR,i and RS_OL,i to the vehicle via the second interface. This development enables an updating of said above-mentioned data, wherein changes in the road traffic network due to vehicles with a lane keeping assistance system according to the invention are transmitted advantageously automatically to the central station.

Advantageously, the radar system has multiple laterally scanning radar sensors which in each case are distributed laterally with respect to the vehicle along the vehicle longitudinal axis. Thus, shadowing or covering of a clear radar view onto the objects can be partially compensated. For example, if the vehicle is driving in a center lane, the lateral radar view in the front area of the vehicle can be covered by another vehicle travelling forward on the side. In this case, radar sensors which are arranged in the lateral rear portion of the vehicle can nevertheless have a clear lateral radar view.

A development of the lane keeping assistance system is characterized in that the evaluation unit for identifying the objects OR and OL acquired by the radar system as objects OR_i, OL_i acquires, with a counter Z_L, the number ANZ_OL of the objects OL acquired laterally to the left, and, with a counter Z_R, the number ANZ_OR of the objects OR acquired laterally to the right, wherein the quantities ANZ_OL and ANZ_OR are taken into consideration in the determination of the vehicle position P2(t). This is used advantageously for estimating a longitudinal position on the route section being traveled by the vehicle, in particular in the case of multiple similar radar targets OL, OR (for example, guiderail mounts) arranged adjacently next to the current traffic lane. Advantageously, the count is started anew, if one of the objects acquired by the radar system has been identified unequivocally.

Another aspect of the invention relates to a vehicle, in particular a motor vehicle, with a lane keeping assistance system as described above.

Another aspect of the invention relates to a method for the transverse control of a vehicle. This method includes the steps: determination of a current first position P1(t) of the vehicle in a road traffic network with a position accuracy ΔP1: P1(t)=P1(t)±ΔP1, providing of a target trajectory ST(t) of the vehicle in the road traffic network, providing of georeferenced position data P_OR,i, P_OL,i of objects OR_i of a right traffic lane boundary and of georeferenced position data of objects OL_i of a left traffic lane boundary, and of 2D or 3D radar signatures RS_OR,i and RS_OL,i, of these objects OR_i, OL_i, for the route section of the road traffic network being traveled by the vehicle, wherein the georeferenced position data P_OR,i, P_OL,i have a position accuracy ΔP2 of <0.15 m, where ΔP2<ΔP1, i=1, 2, 3, . . . , scanning via a radar system of a right and of a left lateral environment of the vehicle for the determination of distances D_OR to objects OR present laterally to the right of the vehicle and the radar signatures RS_OR thereof, and of distances D_OL of objects OL present laterally to the left of the vehicle and the radar signatures RS_OL thereof, based on the first position P1(t), the provided data P_OR,i, P_OL,i, RS_OR,i and RS_OL,i and the determined data D_OR, RS_OR, D_OL, RS_OL, determination of a second position P2(t) of the vehicle, the position accuracy of which has the position accuracy ΔP2 at least in one dimension, and performance of the transverse control of the vehicle taking into consideration the target trajectory ST(t) and the position P2(t).

Developments and advantages of the invention result from an analogous and appropriate transfer of the preceding explanations of the lane keeping assistance system.

The aim of the invention is achieved moreover by a computer system with a data processing device, wherein the data processing device is designed in such a manner that a method, as described above, is carried out on the data processing device.

In addition, the aim of the invention is achieved by a digital storage medium with electronically readable control signals, wherein the control signals can thus work together with a programmable computer system so that a method, as described above, is carried out.

Furthermore, the aim of the invention is achieved by a computer program product with a program code stored on a machine readable support for carrying out the method, as described above, if the program code is executed on a data processing device.

Finally, the invention relates to a computer program with program codes for carrying out the method, as described above, if the program runs on a data processing device. For this purpose, the data processing device can be designed as any computer system known from the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional advantages, features, and details result from the following description, wherein—if applicable in reference to the drawings—at least one embodiment example is described in detail. Identical, similar and/or functionally equivalent parts are provided with identical reference numerals.

In the drawings:

FIG. 1 shows a schematic design of a lane keeping assistance system according to the invention; and

FIG. 2 shows a schematic flowchart of a method according to the invention.

DETAILED DESCRIPTION

FIG. 1 shows a schematic design of an inventive lane keeping assistance system for a vehicle, including a means 101 for determining a current first position P1(t) of the vehicle in a road traffic network with a position accuracy ΔP1: P1(t)=P1(t)±ΔP1, a first interface 102 for the providing of a target trajectory ST(t) of the vehicle in the road traffic network, a second interface for the providing of georeferenced position data P_OR,i, P_OL,i of objects OR_i of a right traffic lane boundary and of georeferenced position data of objects OL_i of a left traffic lane boundary, and 2D or 3D radar signatures RS_OR,i and RS_OL,i of these objects OR_i, OL_i for the route section of the road traffic network being traveled by the vehicle, wherein the georeferenced position data P_OR,i, P_OL,i have a position accuracy ΔP2, where ΔP2<ΔP1, i=1, 2, 3, . . . , a radar system 103 for scanning a right and a left lateral environment of the vehicle for the determination of distances D_OR to objects OR present laterally to the right of the vehicle and the radar signatures RS_OR thereof, and of distances D_OL to objects OL present laterally to the left of the vehicle and the radar signatures RS_OL thereof, an evaluation unit 104, via which initially, based on the first position P1(t), the provided data P_OR,i, P_OL,i, RS_OR,i and RS_OR,i, and the determined data D_OR, RS_OR, D_OL, RS_OL, an identification of the acquired objects OR and OL as objects OR_i, OL_i is performed, and based thereupon, a second position P2(t) of the vehicle is determined, the position accuracy of which has the position accuracy ΔP2 at least in one direction, and a control device 105 for the transverse control of the vehicle, via which the transverse control of the vehicle occurs taking into consideration the target trajectory ST(t) and the position P2(t).

FIG. 2 shows a schematic flowchart of an inventive method for the transverse control of a vehicle. The method includes the following steps. In a step 201, a determination of a current first position P1(t) of the vehicle in a road traffic network occurs with a position accuracy ΔP1: P1(t)=P1(t)±ΔP1. In a step 202, a providing of a target trajectory ST(t) of the vehicle in the road traffic network occurs. In a step 203, a providing of georeferenced position data P_OR,i, P_OL,i of objects OR_i of a right traffic lane boundary and of georeferenced position data of objects OL_i of a left traffic lane boundary, and of 2D or 3D radar signatures RS_OR,i and RS_OL,i of these objects OR_i, OL_i occurs, for the route section of the road traffic network being traveled by the vehicle, wherein the georeferenced position data P_OR,i, P_OL,i have a position accuracy ΔP2 of <0.15 m, where ΔP2<ΔP1, i=1, 2, 3, . . . . In a step 204, using a radar system, a scanning of a right and of a left lateral environment of the vehicle occurs for the determination of distances D_OR to objects OR present laterally to the right of the vehicle and the radar signatures RS_OR thereof, and of distances D_OL of objects OL present laterally to the left of the vehicle and the radar signatures RS_OL thereof. In a step 205, based on the first position P1(t), the provided data P_OR,i, P_OR,i, RS_OR,i and RS_OL,i, and the determined data D_OR, RS_OR, D_OL, RS_OL, a determination of a second position P2(t) of the vehicle occurs, the position accuracy of which has the position accuracy ΔP2 at least in one direction. In a step 206, a performance of the transverse control of the vehicle occurs, taking into consideration the target trajectory ST(t) and the position P2(t).

Although the invention was illustrated and explained in further detail by preferred embodiments, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by the person skilled in the art, without leaving the scope of protection of the invention. Therefore, it is clear that numerous variation possibilities exist. It is also clear that embodiments mentioned as example represent in fact only examples which in no way should be taken as a limitation of, for example, the scope of protection, the application possibilities or the configuration of the invention. Instead, the above description and the description of figures enable the person skilled in the art to concretely implement the exemplary embodiments, wherein the person skilled in the art, in the knowledge of the disclosed inventive idea, can make various changes, for example, with regard to the function or the arrangement, in an exemplary embodiment of mentioned examples, without leaving the scope of protection which is defined by the claims and their legal equivalents such as, for example, further explanations in the description.

Claims

1. A lane keeping assistance system for a vehicle, the system comprising:

a means for determining a current first position P1(t) of the vehicle in a road traffic network with a position accuracy ΔP1: P1(t)=P1(t)±ΔP1;

a first interface to provide a target trajectory ST(t) of the vehicle in the road traffic network;

a second interface to provide georeferenced position data POR,i and POL,i of objects ORi of a right traffic lane boundary and georeferenced position data of objects OLi of a left traffic lane boundary, and 2D or 3D radar signatures RSOR,i and RSOL,i of the objects ORi and OLi for a route section of the road traffic network being traveled by the vehicle, wherein the georeferenced position data POR,i and POL,i have a position accuracy of ΔP2, where ΔP2<ΔP1, i=1, 2, 3,...;

a radar system to scan a right and a left lateral environment of the vehicle to determine distances DOR to objects OR present laterally to the right of the vehicle and radar signatures RSOR thereof, and distances DOL to objects OL present laterally to the left of the vehicle and radar signatures RSOL thereof;

an evaluation unit, via which initially, based on the first position P1(t), the provided data POR,i, POL,i, RSOR,i and RSOL,i, and the determined data DOR, RSOR, DOL, RSOL, an identification of the objects OR and OL as objects ORi and OLi is performed, and based thereupon, a second position P2(t) of the vehicle is determined, the position accuracy of which has the position accuracy ΔP2, at least in one dimension; and

a control device to perform transverse control of the vehicle taking into consideration the target trajectory ST(t) and the position P2(t).

2. The lane keeping assistance system according to claim 1, wherein the means for determining the first position P1(t) is designed based on data of a satellite navigation system, or based on optical environment data of the vehicle, or based on radar data, or based on dead reckoning data, or a combination thereof.

3. The lane keeping assistance system according to claim 1, wherein the objects ORi and OLi are guardrails, vertical guardrail supports, curbstones, concrete deflectors, pylons, metal fences, noise control walls, side walls or radar reflectors, retroreflectors, corner reflectors, poles of traffic signs, overhead sign structures, or roadside emergency telephones.

4. The lane keeping assistance system according to claim 1, wherein the radar signatures RSOR,i and RSOR,i of the objects ORi and OLi were converted based on radar signatures acquired by a sensor on board an aircraft or on board a satellite in top view and converted to radar signatures acquirable by the radar system of the vehicle.

5. The lane keeping assistance system according to claim 1, wherein the evaluation unit is designed and set up for a plausibility verification, wherein probabilities W(OR) and W(OL) of an unequivocal identification of objects OR and OL are determined in each case as one of the objects ORi and OLi based on the determined radar signatures RSOR and RSOL, the provided radar signatures RSOR,i and RSOR,i and the first position P1(t), wherein, for the determination of the second position P2(t), only those objects OR and OL are used, the probabilities W(OR) and W(OL) of which are above a predetermined limit value G1, and wherein for objects OR and OL, the probabilities W(OR) and W(OL) of which in each case are below the predetermined limit value G1, a warning signal WARN is generated.

6. The lane keeping assistance system according to claim 5, wherein, in the case in which the evaluation unit has determined the position P2(t) at a time step t0, and for time steps tk greater than to, where tk=tk−1+Δt, k=1, 2,..., and Δt:=time increment, the warning signal WARN is generated, the evaluation unit for these time steps tk determines a position P2′(tk), where the control device carries out the transverse control of the vehicle at least for a predetermined period of time ZS based on the position P2′(tk).

P2′(tk)=P2′(tk−1)+{dot over (P)}1(tk−1)Δt, and  (1)

7. The lane keeping assistance system according to claim 1, wherein:

via a third interface, data is provided, which enables an optical and/or ultrasound characterization of the objects ORi and OLi;

an optical system OPT and/or an ultrasound system US is/are present for scanning the right and the left lateral environment of the vehicle for the determination of distances DR,OR,OPT and DR,OR,US to objects OR present laterally to the right of the vehicle and for the identification thereof as objects ORi, and of distances DL,OR,OPT and DL,OR,US to objects OL present laterally to the left of the vehicle and for the identification thereof as objects OLi; and

in determination of the second position P2(t), the evaluation unit takes into consideration the distances DR,OR,OPT, DR,OR,US, DL,OR,OPT, and DL,OR,US to the respective identified objects ORi and OLi.

8. The lane keeping assistance system according to claim 1, wherein the evaluation unit is designed and set up in such a manner that a transmission to a central station is made, indicating that, with the radar system, at positions P1(t) or P2(t), objects OR and/or OL were determined, which are not identifiable as objects ORi and/or OLi and/or that, with the radar system, at positions P1(t) or P2(t), no objects OR and/or OL were determined, which, however, should be present as objects ORi and/or OLi.

9. The lane keeping assistance system according to claim 1, wherein, in identification of the objects OR and OL acquired with the radar system, the evaluation unit acquires, as objects ORi and OLi, with a counter ZL, the number ANZOL of the objects OL acquired laterally to the left, and with a counter ZR, the number ANZOR of the objects OR acquired laterally to the right, wherein the quantities ANZOL and ANZOR are taken into consideration in the determination of the vehicle position P2(t).

10. A method for the transverse control of a vehicle, the method comprising:

determining a current first position P1(t) of the vehicle in a road traffic network with a position accuracy ΔP1: P1(t)=P1(t)±ΔP1;

providing a target trajectory ST(t) of the vehicle in the road traffic network;

providing georeferenced position data POR,i and POL,i of objects ORi of a right traffic lane boundary and georeferenced position data of objects OLi of a left traffic lane boundary, and 2D or 3D radar signatures RSOR,i and RSOR,i of the objects ORi OLi, for a route section of the road traffic network being traveled by the vehicle, wherein the georeferenced position data POR,i and POR,i have a position accuracy ΔP2, where ΔP2<ΔP1, i=1, 2, 3,...;

scanning, using a radar system, a right and a left lateral environment of the vehicle for determination of distances DOR to objects OR present laterally to the right of the vehicle and radar signatures RSOR thereof, and distances DOL to objects OL present laterally to the left of the vehicle and radar signatures RSOL thereof;

determining a second position P2(t) of the vehicle having a position accuracy ΔP2, at least in one dimension, based on the first position P1(t), the provided data POR,i, POL,i, RSOR,i and RSOL,i, and the determined data DOR, RSOR, DOL, and RSOL; and

performing transverse control of the vehicle taking into consideration the target trajectory ST(t) and the position P2(t).